I received an interesting link from Richard M part of his comment is below the rest is HERE.
Richard M Says:
November 24, 2008 at 10:35 pm e
I believe there is some hope for one bio-feul … algae. It has significantly better output than does corn, soy, etc. There is a new tecnology currently being test marketed that uses a vertical arrangement to get more output. They claim 33,000 gals/acre/year.
The great thing about comments on a small blog like mine is that I read each and every one. Along with my natural lack of political correctness I also am unafraid of being wrong. I do it quite often as my wife will happily tell you. Check out the link above, it is pretty interesting.
They claim 33,000 gallons per acre of vegetable oil created using a cool structure which stacks the algae in tubes. This is a huge claim considering that corn produces like 50 gallons per acre or something. Pond algae was the previous best at an inflated 900 gallons of oil per acre. Pretty exciting stuff if it’s true really.
Well we know that bio is a form of solar. Typically there is a very low conversion rate for sunlight into the oil, a bunch of light energy is wasted and a bunch more is put into plant proteins and other things not related to the final product – oil. So the first thing I did was check on how much sunlight energy per acre we can count on. These are just estimates- back of the napkin calcs – but they will give us a smell test.
Direct high noon sunlight is about 1000 Watts/m^2 on a clear day.
If we have 12 hours of top quality sunlight
1000 Watts/m^2* 12 hr/day * 365days/yr* 3600 sec/hour = 15,768,000,000 Watt-s /m^2
Then we assume a cosine distribution for daylight intensity of 63% of peak energy (an optics thing, the approximate average of the cos function)
Assume again that most places will only receive 70% of this amount of light. (also high estimate)
15,768,000,000 Watt-s /m^2* .63 * .7 = 6,953,688,000 Watt-Sec/m^2
1 acre = 4047 sq meters
28,141,575,000,000 Watt-Sec/acre or — Joules per acre in proper units.
How many Joules per acre are there in 33,000 gallons of vegetable oil. Well my 5 minute search didn’t reveal any value for algae veggie oil but it did reveal that wikipedia was using my guesstimated value of 1 gal veggie oil to 1 gal gasoline. They are both hydrocarbons after all. Ripping hydrogen off a carbon chain (oils are to my knowledge all carbon chain based) and combining with oxygen produces the nearly the same energy from nearly every oil type fuel. In college grad school I taught a fuels and lubes lab to keep shoes on my feet.
Well gas is about 121,000,000 joules per gallon so we get 33,000*121,000,000 = 3,993,000,000,000 Joules per acre.
This means that 3,993,000,000,000/28,141,575,000,000 * 100 =14.1% of the total sunlight is converted into oil. This is a huge number.
Look at the system they used.
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